CDK9 inhibition blocks the initiation of PINK1-PRKN-mediated mitophagy by regulating the SIRT1-FOXO3-BNIP3 axis and enhances the therapeutic effects involving mitochondrial dysfunction in hepatocellular carcinoma.

Mitophagy is a type of selective macroautophagy/autophagy that degrades dysfunctional or excessive mitochondria. Regulation of this process is critical for maintaining cellular homeostasis and has been closely implicated in acquired drug resistance. However, the regulatory mechanisms and influences of mitophagy in cancer are still unclear. Here, we reported that inhibition of CDK9 blocked PINK1-PRKN-mediated mitophagy in HCC (hepatocellular carcinoma) by interrupting mitophagy initiation. We demonstrated that CDK9 inhibitors promoted dephosphorylation of SIRT1 and promoted FOXO3 protein degradation, which was regulated by its acetylation, leading to the transcriptional repression of FOXO3-driven BNIP3 and impairing the BNIP3-mediated stability of the PINK1 protein. Lysosomal degradation inhibitors could not rescue mitophagy flux blocked by CDK9 inhibitors. Thus, CDK9 inhibitors inactivated the SIRT1-FOXO3-BNIP3 axis and PINK1-PRKN pathway to subsequently block mitophagy initiation. Moreover, CDK9 inhibitors facilitated mitochondrial dysfunction. The dual effects of CDK9 inhibitors resulted in the destruction of mitochondrial homeostasis and cell death in HCC. Importantly, a novel CDK9 inhibitor, oroxylin A (OA), from Scutellaria baicalensis was investigated, and it showed strong therapeutic potential against HCC and a striking capacity to overcome drug resistance by downregulating PINK1-PRKN-mediated mitophagy. Additionally, because of the moderate and controlled inhibition of CDK9, OA not led to extreme repression of general transcription and appeared to overcome the inconsistent anti-HCC efficacy and high normal tissue toxicity that was associated with existing CDK9 inhibitors. All of the findings reveal that mitophagy disruption is a promising strategy for HCC treatment and OA is a potential candidate for the development of mitophagy inhibitors.Abbreviations: BNIP3: BCL2 interacting protein 3; CCCP: carbonyl cyanide p-trichloromethoxy-phenylhydrazone; CDK9: cyclin dependent kinase 9; CHX: cycloheximide; CQ, chloroquine; DFP: deferiprone; DOX: doxorubicin; EBSS: Earle's balanced salt solution; E64d: aloxistatin; FOXO3: forkhead box O3; HCC: hepatocellular carcinoma; HepG2/ADR: adriamycin-resistant HepG2 cells; MMP: mitochondrial membrane potential; mito-Keima: mitochondria-targeted and pH-sensitive fluorescent protein; MitoSOX: mitochondrial reactive oxygen species; OA: oroxylin A; PB: phosphate buffer; PDX: patient-derived tumor xenograft; PINK1: PTEN induced kinase 1; POLR2A: RNA polymerase II subunit A; p-POLR2A-S2: Ser2 phosphorylation of RNA polymerase II subunit A; PRKN: parkin RBR E3 ubiquitin protein ligase; SIRT1: sirtuin 1.

Sublethal heat stress-induced O-GlcNAcylation coordinates the Warburg effect to promote hepatocellular carcinoma recurrence and metastasis after thermal ablation.

The malignant transformation of residual hepatocellular carcinoma (HCC) cells after thermal ablation is considered as the main factor promoting postoperative HCC progression, which greatly limits the improvement of long-term survival, and at present there is no effective targeted therapeutic strategies. The Warburg effect is a metabolic feature correlated highly with malignant transformation (e.g. epithelial-to-mesenchymal transition [EMT]). Here, we showed that sublethal heat stress triggered a stronger Warburg effect of HCC cells, which contributed to the thermotolerance and invasion of HCC cells. Sublethal heat stress-induced O-GlcNAcylation was involved in this process. Such enhanced Warburg effect in HCC cells may be eliminated through O-GlcNAcylation inhibition, resulting in impaired thermotolerance and EMT, and thereby preventing tumor recurrence and metastasis of HCC-bearing mice after insufficient thermal ablation. Finally, we present evidence that sublethal heat stress-induced O-GlcNAcylation regulates the Warburg effect in HCC cells by promoting hypoxia-inducible factor 1α (HIF-1α) stability. In conclusion, the present study suggests that O-GlcNAcylation coordinates the Warburg effect to promote HCC progression after thermal ablation, which may serve as a novel potential target for controlling postoperative HCC recurrence and metastasis.

Medium or Large Hepatocellular Carcinoma: Sorafenib Combined with Transarterial Chemoembolization and Radiofrequency Ablation.

Purpose To determine the safety and efficacy of sorafenib combined with transarterial chemoembolization (TACE) and radiofrequency ablation (RFA) (hereafter, S-TACE-RFA) in patients with medium or large (range, 3.1-7.0 cm in diameter) hepatocellular carcinoma (HCC). Materials and Methods This retrospective study evaluated the medical records of consecutive patients with medium or large HCC who underwent S-TACE-RFA or combined TACE and RFA (hereafter, TACE-RFA) from January 2010 to December 2014. Sorafenib was started 3-5 days after TACE, and RFA was performed 1-2 weeks after TACE. Treatment complications, recurrence-free survival (RFS), and overall survival (OS) in patients who underwent S-TACE-RFA were compared with those in patients who underwent TACE-RFA. Results Of the 174 patients who underwent S-TACE-RFA or TACE-RFA, 106 who met the eligibility criteria were included in this study. Among them, 40 underwent S-TACE-RFA and 66 underwent TACE-RFA. The patients who underwent S-TACE-RFA had longer RFS (median, 24.0 vs 10.0 months; P = .04) and better OS (median, 63.0 vs 36.0 months, P = .048) than those who underwent TACE-RFA. S-TACE-RFA and α-fetoprotein level were independent prognostic factors for survival in uni- and multivariable analyses. The rate of complications in patients who underwent S-TACE-RFA was similar to that in patients who underwent TACE-RFA (22.5% vs 18.2%, P = .59). Conclusion S-TACE-RFA resulted in longer RFS and better OS than did TACE-RFA in patients with medium or large HCC. © RSNA, 2018 Online supplemental material is available for this article.

Early prediction of survival in hepatocellular carcinoma patients treated with transarterial chemoembolization plus sorafenib.

AIM: To identify clinical biomarkers that could early predict improved survival in patients with advanced-stage hepatocellular carcinoma (HCC) treated with transarterial chemoembolization combined with sorafenib (TACE-S). METHODS: We retrospectively evaluated the medical records of consecutive patients with advanced-stage HCC who underwent TACE-S from January 2012 to December 2015. At the first follow-up 4-6 wk after TACE-S (median, 38 d; range, 33-45 d), patients exhibiting the modified Response Evaluation Criteria in Solid Tumors (mRECIST)-evaluated complete response, partial response, and stable disease were categorized as early disease control. At this time point, multiple variables were analyzed to identify the related factors affecting survival. RESULTS: Ninety-five patients were included in this study, and 60 of these patients achieved early disease control, with an overall disease control rate (DCR) of 63.2%. Patients who got sorafenib at the first TACE (no previous TACE) and patients without portal vein tumor thrombus (PVTT) had a higher DCR than those who underwent previous TACE before TACE-S (72.4% vs 48.6%, P = 0.019) and those with PVTT (75.5% vs 50.0%, P = 0.010). Early disease control after TACE-S, no previous TACE, and no PVTT were the independent prognostic factors for survival in the uni- and multivariate analyses. CONCLUSION: The first follow-up 4-6 wk after TACE-S can be used as the earliest time point to assess the response to TACE-S, and patients with mRECIST-evaluated early disease control, no previous TACE, and no PVTT had better survival.

Photoluminescence mechanism and applications of Zn-doped carbon dots.

Heteroatom-doped carbon dots (CDs) with excellent optical characteristics and negligible toxicity have emerged in many applications including bioimaging, biosensing, photocatalysis, and photothermal therapy. The metal-doping of CDs using various heteroatoms results in an enhancement of the photophysics but also imparts them with multifunctionality. However, unlike nonmetal doping, typical metal doping results in low fluorescence quantum yields (QYs), and an unclear photoluminescence mechanism. In this contribution, we detail results concerning zinc doped CDs (Zn-CDs) with QYs of up to 35%. The zinc ion charges serve as a surface passivating agent and prevent the aggregation of graphene π-π stacking, leading to an increase in the QY of the Zn-CDs. Structural and chemical investigations using spectroscopic and first principle simulations further revealed the effects of zinc doping on the CDs. The robust Zn-CDs were used for the ultra-trace detection of Hg2+ with a detection limit of 0.1 µM, and a quench mechanism was proposed. The unique optical properties of the Zn-CDs have promise for use in applications such as in vivo sensing and future phototherapy applications.

Safety and Efficacy of Transarterial Chemoembolization Combined with CT-Guided Radiofrequency Ablation for Hepatocellular Carcinoma Adjacent to the Hepatic Hilum within Milan Criteria.

PURPOSE: To retrospectively evaluate safety and efficacy of conventional transarterial chemoembolization with ethiodized oil (Lipiodol) combined with CT-guided radiofrequency (RF) ablation for hepatocellular carcinoma (HCC) adjacent to the hepatic hilum. MATERIALS AND METHODS: Between January 2007 and December 2010, conventional transarterial chemoembolization combined with CT-guided RF ablation was performed in 40 patients with HCC adjacent to the hepatic hilum within Milan criteria (group A). Major complications, complete tumor ablation rate, local tumor progression rate, and overall survival were compared with 107 patients with HCC nonadjacent to the hepatic hilum (group B) treated by conventional transarterial chemoembolization combined with CT-guided RF ablation during the same period. RESULTS: Major complications included one case of large hepatic artery-portal vein fistula in group A (2.5%; 1/40) and one case of acute portal vein thrombosis, left heart failure, and tumor seeding in group B (2.8%; 3/107); the difference was not significant between the two groups (P = 1.000). There were no significant differences between the two groups in complete tumor ablation rate (80.0% vs 86.0%; P = .374), local tumor progression rates (1-year, 12.5% vs 14.1%; 2-year, 28.2% vs 24.2%; 3-year, 32.0% vs 27.6%; P = .723), and overall survival (1-year, 92.3% vs 91.8%; 3-year, 79.1% vs 79.3%; 5-year, 59.5% vs 58.4%; P = .555). CONCLUSIONS: Conventional transarterial chemoembolization combined with CT-guided RF ablation was safe and effective in selected patients with HCC adjacent to the hepatic hilum within Milan criteria.

[Clinical observation of transcatheter arterial chemoembolization plus sorafenib in the treatment of advanced hepatocellular carcinoma with different types of portal vein tumor thrombosis].

OBJECTIVE: To explore the efficacy and safety of transcatheter arterial chemoembolization (TACE) plus sorafenib in the treatment of advanced hepatocellular carcinoma with different types of portal vein tumor thrombosis. METHODS: A total of 32 patients of advanced hepatocellular carcinoma with tumor thrombosis in portal vein were retrospectively analyzed. All of them took oral sorafenib after TACE. They were divided into 3 groups according to imaging examinations of tumor thrombosis in portal vein. Tumor thrombosis in main portal vein was group A, tumor thrombosis in right/left portal branch group B and tumor thrombosis in the second branch of portal vein group C. Tumor response rate, disease control rate (DCR), overall survival (OS) and time to tumor progression (TTP) was followed up. Liver functions were compared with the pre-treatment level. The occurrences of adverse events were recorded. RESULTS: DCR was 20.0% (Group A), 70.0% (Group B) and 91.7 % (Group C) at 2 months post-treatment. DCR in groups B and C had significant differences with group A (P < 0.05). The median OS was 3 (Group A), 9 (Group B) and 14 months (Group C) and the median TTP 0 (Group A), 3 (Group B) and 6 months (Group C) respectively. The median OS and median TTP were significantly longer in Groups B and C than those in Group A (P < 0.05). Liver function at 2 months post-treatment had no statistical difference with the baseline. The most common adverse effects included hand foot skin reaction (n = 23, 3 cases of grade 3), hypertension (n = 3), diarrhea (n = 25, 3 cases of grade 3), hair loss (n = 12), oral ulcers (n = 1) and gastrointestinal bleeding (n = 2). CONCLUSION: The combined use of TACE and sorafenib is both safe and efficacious in the treatment of advanced hepatocellular carcinoma with tumor thrombosis in portal vein. And it may prolong OS and TTP in hepatocellular carcinoma with tumor thrombosis in right/left portal vein and second branch of portal vein.

TanshinoneIIA ameliorates inflammatory microenvironment of colon cancer cells via repression of microRNA-155.

TanshinoneIIA, an active component derived from a traditional Chinese medicine, has anti-inflammatory and anti-cancer effect. However, the mechanisms underlying the interaction between anti-inflammation and anti-cancer of TanshinoneIIA remain elusive. In the present study, a cell model of inflammation between macrophages and colon cancer cells was used. The results showed that TanshinoneIIA inhibited the proliferation of inflammation-related colon cancer cells HCT116 and HT-29 by decreasing the production of inflammatory cytokines tumor necrosis factor α (TNF-α) and interleukin 6 (IL-6), which generated by macrophage RAW264.7 cell line. We identified Phosphatidylinositol-3, 4, 5-trisphosphate 5-phosphatase 1 (SHIP1) was a bona fide target of miR-155. TanshinoneIIA restored the down-regulated level of SHIP1 protein after lipopolysaccharide (LPS)-stimulation in RAW264.7 cells. MicroRNA-155 (miR-155) was up-regulated in macrophages, possibly due to the concomitant increase of PU.1, a transcriptional activator of miR-155, accounting for decreased SHIP1. Treatment with TanshinoneIIA prevented increased PU.1 and hence increased miR-155, whereas aspirin could not. These findings support that the interruption of signal conduction between activated macrophages and colon cancer cells could be considered as a new therapeutic strategy and miR-155 could be a potential target for the prevention of inflammation-related cancer.